If either screen is showing signs of being blotchy, cracked or colors running together then this is a malfunction in the LCD screen. You need to remove the broken screen and replace it with a new one. Follow this repair guide for assistance. Top Screen and Bottom Screen

Lines on either screen are generally caused by the image on the screen being broken due to malfunctioning imaging parts. This is usually caused by a hard impact such as dropping the device. You may need to replace the LCD screen to repair this problem. Follow this repair guide for assistance. Top Screen and Bottom Screen

Note: If you see lines on your screen which are still showing after you have turned off your device but slowly fade away, this is normal.

If you have scratches on the top screen this can be replaced easily if you buy a new screen from the Nintendo website. To fix this portion of the DS you will need to dissemble it first to get to the outer casing. Follow this repair guide for assistance. Top Screen

If the bottom screen is scratched it is a bigger problem because that is the touch screen and does not have a protective plastic layer therefore the entire screen will have to be replaced. Follow this repair guide for assistance. Bottom Screen

Make sure that you calibrate the system to the touch of the stylus. It will be delayed or not work properly if this is not done so reset this first before trying other solutions.

It could be due to a screen protector on the bottom screen. These protector sheets have the ability to lower the sensitivity of the touch screen. However, if you decide to remove this protective layer keep in mind that some sheets leave a sticky residue that must be cleaned properly to make the touch screen work properly again.

You could also have something lodged into the sides of the screen. Make sure to hold the DS up and tilt it around so that you can see all the edges of the screen, making sure the connection of the screen to the plastic case are perfectly touching with no foreign debris or any kind. If foreign debris is found gently take a toothbrush and press lightly down on the screen where the foreign object is while brushing it out.

When the screen is dark this means that the device is in sleep mode and this usually happens when the lid is closed. If it continues to be in sleep mode when the lid is open then something is wrong in the hardware or software of the device. Most likely between the connections of the lid to the bottom circuit board in the bottom part of the DS.

Since the bottom screen is a touch screen is is not as bright as the top due to an extra layer of sensitivity for the bottom screen.

Try looking at the bottom screen with the DS flat surface and looking right at it. By changing your angle to this point of view the image should become brighter.

If you are trying to play a Game Boy Advanced game then you can switch the settings so that the game is shown on the top brighter screen.

Screen protectors also have the ability to make the bottom touch screen appear different looking. Make sure you are using a Nintendo Licensed screen protector because they are made to be compatible with all processes of the DS, most importantly the sensitivity of the touch screen.

This is usually a broken pixel and the problem should not spread further in the screen. If it does not interrupt or distract in game play then it is not worth fixing. However, if you do want to get it fixed, the LCD screen will need to be replaced. Follow this repair guide for assistance. Top Screen and Bottom Screen

Use a toothbrush without any liquid substances and gently brush the sides of the screen until the debris is cleared. Make sure to hold the device up to help it fall out. Also you might need to push down on the screen slightly to free the debris.

Note: Make sure you recalibrate the system after doing this because it could have changed some of the settings for the touch screen.

If you are experiencing problems with the power with the DS either with the battery or power in general make sure you check to see if it is being properly charged before repair:

Check the AC Adapter for any damage

Try another outlet for plugging in the AC Adapter

If you can, try a different AC Adapter

Battery lifetime:

Gradual battery loss: This is expected wear on the Nintendo DS because after about 500 charges the battery life will gradually decrease over time. You may want to replace the battery if the battery loss is extensive. Follow this repair guide for assistance. Battery

Quick battery loss: This is usually caused by liquid spills or damage to the device. Open battery and separate it from the Nintendo DS body letting it dry. If the battery still does not work after drying it needs to be replaced. Follow this repair guide for assistance. Battery

Note: If you have quick battery loss but none of the above apply then you should replace your battery. Follow this repair guide for assistance. Battery

If you have a problem with your headphones or speakers check the following things before repair:

Make sure volume is all the way up (all the way to the right).

Check your game settings.

Check the system settings.

For speakers make sure you do not have headphones plugged in.

For headphones make sure that they work properly by checking to see if they work in another device or by seeing if the actual speakers work by themselves. If the speakers work by themselves for the device then something is broken in the headphones.

Note: If only one speaker works in the DS then you should get the speakers replaced.

If the microphone is not responding make sure to check the game guide to see if the game you are playing is compatible to use a microphone with.

If your buttons are not responding for one game make sure to check the manual for the game because not all games use the buttons to function.

If your buttons are not responding for all games then your buttons will need to be repaired. Some causes of this might be liquid spills or dropping the device.

If your buttons are sticking then you should take careful procedures to clean them. Follow this repair guide for assistance and use a light toothbrush to gently clean the buttons.A Guide Step 11 is where you should have full access to the buttons and you would not have to go any further in this repair guide to clean the buttons. You should be able to separate the buttons from the casing and this will help you to clean off any sticky residue.

If you are having trouble getting Game Boy games to work in the DS system it might be due to the fact that only Game Boy Advanced games work in the DS. Game Boy Color and Game boy original games are not compatible.

Note If you are having trouble with a Game Boy Advanced game fitting into the slot, make sure it is a compatible version and does not have any foreign material blocking the connection.

Make sure for all DS games that you hear a click when inserting the game because this means that it was inserted completely. If this only happened with one game there could be a malfunction in the game card and it might need to be replaced.

It is normal for a game to have an image that is mixed up or malfunctioning occasionally. Take the game out and reinsert it and this should solve the problem. If it continues to happen your DS needs to be repaired.

Note:

Make sure you are using Nintendo licensed accessories because often times non compatible pieces can mess with the system.

Make sure there is not foreign material wedged between the DS game card and the game slot on the device.

Make sure that you have tried to recalibrate the stylus to your movements. Also remember that the stylus is hard to get used to but eventually you should get the hang of it. If you have tried these things but the game is still not responding it is most likely an issue with the LCD touch screen and the connections within the DS therefore your system needs repair.